ALEXANDRE DUPOUY
His pseudonym was Monsieur X. His subject, the sex workers of Paris.

"The mysterious Mr. X is an amateur and yet so professional by the quality of his images," French collector Alexandre Dupouy explained to the Huffington Post. "A photographer of the 30s, yet so close to our contemporary voyeurism. Obsessional yet attaining a rare degree of complicity with his models."

Dupouy, whose shop The Tears of Eros specializes in erotic and pornographic imagery, stumbled upon Monsieur X's work by accident. Around 1975, when in his 80s, Monsieur X left his life's work to a Parisian bookseller of similar tastes, including several thousand 18 x 24-centimeter prints, about a hundred 6 x 13-centimeter stereoscopic prints, and two 10-minute films. The nameless bookseller contacted Dupouy, who acquired the images and agreed to keep the photographer's identity anonymous.

After carefully examining the photos, Dupouy identified certain car models that approximately dated Monsieur X's works between 1925 and 1935. Brothels were legal in Paris until 1946. Thanks to a recognizable balcony, Dupouy ascertained the site of the brothel depicted at 75 Rue Jean Baptiste Pigalle.

ALEXANDRE DUPOUY
Monsieur X's photographs often feature names like Fanfan, Gaby, Gypsi, Jojo, Mado, Mimi, Nenette and Nono scribbled on the back, provide an alluring and sometimes alarming vision of life as a sex worker in early-1900s Paris. Although the images are most often playful, featuring big smiles and frisky poses, they hint at the struggles these young women were subjected to.

"The typical profile was a girl that came to Paris to make money so that she could feed her family back on the farm somewhere in the countryside," Dupouy explained in an interview with Vice. "Hungry and unemployed, the girl often stumbled across a Madame that would promise them shelter and warmth. One would usually end up staying with 10 or 15 girls in the same situation."

At the time, a sex worker earned around 10 times that of a regular worker, Dupouy added. However, the extra income came at a price. Disease was rampant and access to protection was paltry. "Condoms existed, but weren't mandatory. The girls cleaned themselves with something called 'hygienic sponges.' The sponges had, of course, absolutely no efficiency."

Yet, DuPouy explained, the vile working and living conditions these women faced yielded unconventional and wildly intimate friendships.

These girls are used to displaying themselves, caressing themselves, alone or in company. One can guess that they live in the nude, in the same room, the same house.